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A team approach to international health

A team approach to international health

When it comes to issues in international public health, the challenge is more than just one of medicine. Solutions require people from multiple disciplines to work together, along with governmental ministries and often non-profit organizations.

Grant Miller, PhD, an associate professor of medicine, has been working on one such challenge – that of micronutrient deficiency in the Indian state of Tamil Nadu.

“There are at least three ministries that have key responsibility over this area,” Miller says. “We then have to work with an NGO partner, and we have to go out and collect our own data and evaluate how this intervention works.”

Miller works with both the Freeman Spogli Institute for International Studies and the Stanford Institute for Economic Policy Research, and he says the institutes play an important role in supporting interdisciplinary collaborations like this one.

“Stanford makes it very easy to do interdisciplinary research,” he says. “I think the pay off is huge, but it’s not an easy thing to do.”

More faculty talk about the value of collaboration in their work as part of the new Stanford Interdisciplinary website.

Previously: New website chronicles tales of collaborative research and Stanford journalist returns to old post in India – and finds health care still lagging
Video by Worldview Stanford

Global Health, In the News, Infectious Disease, Podcasts

Talking about the Zika virus

Talking about the Zika virus

The Zika virus has been reported in 23 countries and territories in the Americas. Brazil is the hardest hit nation so far with more than 1 million infections. In the continental U.S. the 35 known cases of Zika have been the result of people who have traveled to infected areas and returned to the U.S. No local mosquito-borne transmission has been reported.

Globalization has changed the rapid nature in which viruses spread. To that end, broad calls for action have been engaged. The World Health Organization has declared Zika an international health crisis, and the U.S. Centers for Disease Control and Prevention declared it a Level 1 alert – the highest activation. Earlier this week, President Obama asked Congress to allocate $1.8 billion in emergency finding to vaccine research, surveillance and rapid response programs. The request also includes foreign aid to countries most impacted by Zika.

While the virus is not known to be deadly and most people who contact it will have no symptoms at all, pregnant women are most at risk. To protect their babies, the CDC is warning pregnant women not to travel to areas affected by the virus. There is no vaccine to prevent the disease.

The New York Times yesterday provided an interesting detailed history of the virus’ path since its discovery in 1947, and new information about the virus is emerging every day. Just yesterday, CDC Director Thomas Frieden told the House Foreign Affairs Committee that the CDC has uncovered new evidence supporting the link between Zika and microcephaly, a birth defect in which infants are born with unusually small heads and incomplete brain development.

In this new 1:2:1 podcast I spoke with Stanford infectious disease expert Yvonne Maldonado, MD, about Zika and the latest on the virus. She’s a professor of pediatrics at the school of medicine and the chief of pediatric infectious disease at Stanford Children’s Health.

Previously: Zika outbreak shares key traits with Ebola crisis, Stanford experts point out

Global Health, Infectious Disease, Microbiology, Research, Stanford News

If you gum up a malaria parasite’s protein-chewing machine, it can’t do the things it used to do

If you gum up a malaria parasite's protein-chewing machine, it can't do the things it used to do

chewing gum“Life in the tropics” evokes images of rain forests, palm trees, tamarinds and toucans. It also has a downside. To wit: One-third of the Earth’s population – 2.3 billion people – is at risk for infection with the mosquito-borne parasite that causes malaria.

Thankfully, mortality rates are dropping because of large-scale global intervention efforts. But malaria remains stubbornly prevalent in sub-Saharan Africa and Southeast Asia, where hundreds of millions of people become infected each year and more than 400,000 of them – mostly children younger than 5 – still die from it.

The parasite has the knack of evolving rapidly to develop resistance to each new generation of drugs used to fend it off. Lately, resistance to the current front-line antimalarial drug, artemisinin, is spreading and has now been spotted in a half-dozen Southeast Asian countries.

So it’s encouraging to learn that Stanford drug-development pioneer Matt Bogyo, PhD, and his colleagues have designed a new compound that can effectively kill artemisinin-resistant malaria parasites. Better, exposure to low doses of this substances re-sensitizes them to artemisinin.

By exploiting tiny structural differences between the parasitic and human versions of an intercellular protein-recycling machine called the proteasome, the compound Bogyo’s team has created attacks the malaria parasite while sparing human cells.

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Global Health, Health Policy, In the News, Public Health

Zika outbreak shares key traits with Ebola crisis, Stanford experts point out

Zika outbreak shares key traits with Ebola crisis, Stanford experts point out

An op-ed co-authored by global-health physician Michele Barry, MD, calls attention today to alarming parallels between the outbreaks of Ebola and Zika. In the Los Angeles Times, she and co-author Yanbai Andrea Wang, JD, PhD, write:

Both were detected late… Both disease outbreaks generated sluggish international responses… And in both outbreaks, the heaviest burden fell on vulnerable populations least able to bear it…

These mistakes will continue to repeat, they write, unless significant changes are made:

To build an effective global system for containing infectious diseases like Zika and Ebola, we need to make sure that countries around the world have the surveillance capacity to identify outbreaks before they spiral out of control. That means giving technical and financial assistance to developing countries and having external monitoring and incentives to make sure that capacity is built. We also need to make sure that WHO — the only organization with the representation and legitimacy to do so — is up to the task of leading outbreak response when local forces are overwhelmed.

Zika is a mosquito-borne virus that can cause fever and joint pain and, in some cases, severe birth defects such as microcephaly. Recent cases have been concentrated in South and Latin America, particularly northern Brazil, and on Feb. 1, the World Health Organization declared the outbreak an international public health emergency.

Photos of babies with tiny heads have captured global attention, Barry and Wang note. “Let’s remember the broader systemic shortcomings that got us here in the first place.”

Previously: Ebola: It’s not over, Ebola: This outbreak is different and Stanford team develops a method to prevent the viral infection that causes dengue fever
Photo courtesy of USDA

Cancer, Global Health, Pediatrics, Stanford News

The “little angel” who helps young Latin American children with cancer

The “little angel” who helps young Latin American children with cancer

ZambranoEduardo Zambrano’s spare office in Stanford Hospital displays some of the essentials of his pathology practice: a large microscope which dominates his desktop and a cabinet overflowing with colorful, hand-painted wooden boxes, each one representing a Latin American child with cancer.

Over the last 12 years, Zambrano, MD, has received as many as 1,000 tumor samples from pediatric oncologists in Venezuela and other Latin American countries who treat desperately poor young patients with various forms of cancer. Each sample is carried on a glass slide or embedded in wax, then carefully wrapped in tissue paper and lovingly packaged in a wooden box painted by a patient’s mother or local artisan as a gesture of gratitude. The boxes are covered in suns, stars, flowers and other images of life and hope.

“To me, behind each one of these boxes is a child with cancer, and to know we’ve been able to help them is very special to me,” said Zambrano, chief of pathology at Lucile Packard Children’s Hospital Stanford. An expert in pediatric solid tumors, he volunteers his service on behalf of these youngsters.

A professor of pediatrics and of pathology who came to Stanford a year ago, he said he receives one or two of these boxes a week. He examines the samples under the microscope and then issues a diagnosis, some involving rare cancers. Clinicians ship the samples to him because in these low-resourced countries, they don’t have the means to accurately diagnose the problem.

“Very frequently the diagnosis (from the home country) is either incomplete because they don’t have the resources to perform confirmatory tests or it’s wrong because they don’t have expertise in pediatric tumors,” he said. “It’s frequent that I have to give them a significantly different diagnosis than what they sent.”

Among the most common tumors he sees are pediatric sarcomas, which can originate in various parts of the body; neuroblastomas; lymphomas; and brain tumors.

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Global Health, HIV/AIDS, Infectious Disease

Growing resistance to vital HIV drug raises concern

Growing resistance to vital HIV drug raises concern

tablets-193666_1280HIV resistance to the antiviral tenofovir, one of the mainstays of HIV treatment and prevention, is increasingly common following therapy, particularly in low and middle-income countries, according to a new, multi-national study.

“Public health organizations and global funders have been very effective at expanding antiretroviral drug therapy to increasing proportions of patients in need,” said Robert Shafer, MD, professor of medicine and co-author of the work. “This study highlights the need for efforts to ensure that the regimens used to treat HIV retain their effectiveness for as long as possible.”

Researchers studied 1,926 patients in 36 countries who developed virological failure after taking a first-line regimen containing tenofovir. In this group, tenofovir-resistant strains were found in 60 percent of the patients in sub-Saharan Africa, compared with fewer than 30 percent in Europe and North America. Patients most at risk for tenofovir resistance were those who started therapy late in the progression of the disease or who received tenofovir in combination with drugs less commonly used in upper-income countries.

About two-thirds of the patients with tenofovir-resistant strains also had become resistant to the other two drugs in their regimens, suggesting their treatment had become largely ineffective.

Resistance may develop when patients don’t take their medication regularly, although it may also occur in adherent patients on some of the regimens used in the developing world. People carrying resistant strains can pass them along to others, so that HIV resistance could become even more widespread, the researchers note.

“Tenofovir is a critical part of our armamentarium against HIV, so it is extremely concerning to see such a high level of resistance to this drug,” said lead author Ravi Gupta, MD, at University College London. “It is a very potent drug with few side effects, and there aren’t any good alternatives that can be deployed using a public health approach. Tenofovir is used not only to treat HIV but also to prevent it in high-risk groups, so we urgently need to do more to combat the problem of emerging resistance.”

The researchers say the results reinforce the need for increased drug resistance surveillance in both untreated and treated HIV-positive individuals. They are now working to better understand how these resistant viruses develop and spread.

The study, which involved dozens of researchers and institutions, appears today in the journal Lancet Infectious Diseases. It was co-authored by scientists at the London School of Hygiene and Tropical Medicine and funded by the Wellcome Trust.

Previously: Spread of drug-resistant HIV in Africa and Asia is limited, Stanford research finds, HIV study in Kenyan women: Diversity in a single immune-cell type flags likelihood of getting infected and Study: Chimps teach people a thing or two about HIV resistance
Image by bigblockbobber

Global Health, Pediatrics, Stanford News

Clean water for Dhaka, one pump at a time

Clean water for Dhaka, one pump at a time

Dhaka water 2

More than two years ago, Amy Pickering, PhD, and her Stanford colleagues were just starting to field-test a radical new approach to clean up the contaminated water supply in Dhaka, Bangladesh, and improve the health of the city’s slum dwellers.

Since then, the team has made major progress in the project, which uses a simple, low-cost chlorination system to eliminate dangerous microbes in the city’s drinking water, Pickering said in a recent talk at the Stanford Global Health Research Convening on campus.

Dhaka has notoriously unsafe water supplies, with testing showing that as much of 80 percent of the city’s water is contaminated with E. coli, a major cause of diarrhea, Pickering said. The source: human waste, which is sucked into the city’s water system by cracked, leaky PVC pipes.

“There’s open sewage everywhere,” Pickering told me for a 2013 story in Stanford Medicine magazine. “There’s not a well-functioning sewer system to remove feces from the communities. The kids are playing in it, and it’s very unsafe.”

Her team, which includes a group of Stanford undergraduates, created a simple device, attached to communal water pumps, which infuses a small amount of chlorine into the water to kill viruses and bacteria and most disease-causing pathogens. It’s the first automated chlorine disinfection system in use in a low-income area.

In 2014, the group tested the device over a 10-month period in more than 150 households and found it reduced E. coli contamination by 70 percent, Pickering told more than 100 faculty, students and staff at the recent conference. The event was sponsored by the Stanford Center for Innovation in Global Health.

The researchers are now midway through a much larger trial, funded by the World Bank, to test the health impacts of the purification system in more than 1100 Bangladeshi children under age 5. The researchers are looking at whether the system reduces the incidence of diarrhea, a common cause of childhood death, and improves weight gain among the children, who often suffer from stunted growth because of waterborne illness, said Pickering, now a research scientist at the Stanford Woods Institute for the Environment.

The researchers also have made progress in finding a way to support and sustain use of the purification system. Pickering said the group offered the pumps to local landlords, who could use them to attract potential renters. Some 60 landlords agreed to pay $3 to $5 a month for the pumps, almost enough to cover the cost of the system, she said.

“This was really encouraging to us,” Pickering said. “We weren’t expecting people to be willing to pay this much.”

She also has found some potential commercial partners, including MSR Global Health, a pioneering outdoor company, interested in helping further reduce costs and refining the technology as a prelude to commercially marketing the pumps, she said.

Pickering said she now hopes to expand the project to sub-Saharan Africa, and spread her dream of bringing clean water and good health to low-income residents across the globe.

Previously: Stanford pump project makes clean water no longer a pipe dream, The right tool for the job: Creating a waterborne disease reporting system for Nepal and How cutting the walking time to a water source can reduce childhood mortality in sub-Saharan Africa
Photo courtesy of Amy Pickering

Chronic Disease, Global Health, Medical Apps, Public Health, Public Safety, Research

The right tool for the job: Creating a waterborne disease reporting system for Nepal

Fig 3When I last spoke with cholera expert Eric Jorge Nelson, MD, PhD, he was about to field test a tool to help doctors in Bangladesh diagnose, treat and report cholera outbreaks in real time using a smartphone app. Now that this reporting system is up and running, he’s working to create similar reporting systems for doctors elsewhere. But, as he learned in the remote regions of Nepal, a high-tech approach isn’t always the best approach.

Nelson was invited to Nepal by his colleague Jason Andrews, MD, an infectious disease expert who works with the Dhulikhel Hospital, to share his expertise on recognizing, responding to and containing cholera outbreaks.

Like Bangladesh, Nepal has seasonal outbreaks of waterborne diseases, including cholera, Typhoid, viral hepatitis and dysentery, that ebb and flow with the monsoon seasons. What made the situation in Nepal urgent, Nelson told me, is that waterborne diseases can also arise after natural disasters, and a 7.8 magnitude earthquake struck Nepal last spring and more than 100 aftershocks have hit the region since.

An added complication, Andrews explained, was that Nepal’s government wasn’t scaling up waterborne disease surveillance in the rural areas following the earthquakes. “Our colleagues at Dhulikhel Hospital, by contrast, were extremely proactive and committed to setting up a system before an outbreak hit,” Andrews said.

Nelson was only in Nepal for about 48 hours, but during those two days he and Andrews began to tackle the problem of how to prevent a large-scale cholera outbreak there. At first, it seemed plausible that the smartphone app designed for Bangladesh would work in Nepal — but Nelson said they quickly realized that Nepal’s post-earthquake infrastructure wasn’t suited to a smartphone reporting system.

“There were few resources in Nepal and little time to ramp-up a reporting system,” Nelson said. “Charging a smartphone requires a stable power supply, and although the 3G networks within the city were fine, they weren’t good in the canyons.”

This is where Andrews’ expertise came in. His knowledge of Nepal and experience building surveillance systems with “just the bare bones” (as he put it) helped the team reverse engineer the smartphone app Nelson used in Bangladesh and use elements of it to create a paper-based surveillance system that’s better suited to the post-earthquake situation in rural Nepal.

“This was a risky endeavor,” Andrews said. “We didn’t have funding so we drew upon our own existing resources. Funding takes a while, the earthquake was in April and the monsoon hits in June. If we had waited, the monsoon season would have passed. We realized we could scale this up really quickly with minimal resources and it was worth the risk.”

Now, the team’s paper-based system has been working for several months and Nepal’s government is interested in replicating the model at a larger level.

“I learned two important lessons during my trip to Nepal,” Nelson told me. “I learned the power of winnowing a complicated process, like our smartphone app, down. I also learned how we can broaden what we did in Bangladesh for a wider community.”

He continued: “Hopefully we are emerging from the idea that mobile technology is a panacea. We need to be open to considering high — or low — tech strategies depending on what the on-the-ground situation is. We happened to have two very different design challenges in Bangladesh and Nepal: Mobile was best for Bangladesh and paper was best for Nepal. You have to build what the end-user desires, is feasible and is viable. I think the mhealth field is waking up to this reality.”

Previously: A tale of two earthquakes: Stanford doctor discusses responses to the Nepal and Haiti disastersReporting and treating cholera: Soon, there could be an app for thatDay 1: Arriving in Nepal to aid earthquake victims and Using social media to fight cholera
Photo courtesy of U.u.H. Schmel and R.K. Mahato

Global Health, Health Policy, In the News, Pediatrics, Pregnancy, Women's Health

Ending preventable stillbirth: A Q&A with Stanford global-health expert Gary Darmstadt

Ending preventable stillbirth: A Q&A with Stanford global-health expert Gary Darmstadt

Today, prominent medical journal The Lancet publishes “Ending Preventable Stillbirth,” a series of articles calling for global efforts to greatly reduce fetal deaths that occur late in pregnancy or during labor. The series brings much-needed attention to a medical and societal problem that often goes ignored.

“Millions of women and families around the world have suffered the pain of stillbirth in silence,” said series adviser Gary Darmstadt, MD, a Stanford global-health expert who studies how to improve medical care for pregnant women, infants and children in developing countries.

Darmstadt recently answered my questions about why we should break the silence and work to lower stillbirth rates. “Many of the interventions that avert stillbirths also avert deaths of mothers and newborns,” he said. An edited version of his responses is below.

What’s the biggest misconception about stillbirth?

Perhaps the biggest misconception is that stillbirths don’t matter. There is a tradition of social stigma and lack of awareness of stillbirths that makes it easy to keep them out of sight and out of mind. But an estimated 1.2 million women around the world every year have an intrapartum stillbirth: They enter into labor after a normal pregnancy, with great expectations for a healthy baby and one of the most joyous experiences of a lifetime, only to face sudden devastation when the baby dies during birth. Their experiences matter.

A related misconception is that nothing much can be done to prevent stillbirth, or that prevention will divert scarce resources from other important issues. In fact, three fourths of intrapartum stillbirths around the world could be prevented through means that we take for granted in high income societies — such as skilled medical care before and during delivery — and that also benefit mothers, surviving newborns and children.

Why did the scientists involved in The Lancet’s new series think it was important to break the common pattern of silence, stigma and fatalism around stillbirth?

Stillbirth is a taboo topic in many societies, or worse yet, mothers are blamed for failing to deliver a healthy baby and feel intense social pressure to keep quiet about stillbirth. Their sense of loss and isolation may lead to depression, which in turn has many adverse consequences, including for subsequent pregnancies. On the other hand, many women who have the opportunity to talk about their experience with stillbirth and work through their grief express great relief and renewed hope. When the last Lancet stillbirth series came out five years ago, and women shared their experiences online or in parent support groups — often the first time they had ever shared their experience with stillbirth with anyone — many found this to be immensely healing and empowering. Thus, it was both the science showing the adverse effects of unexpressed and unresolved grief, and the testimonials of women who had experienced the benefits of breaking the silence that I believe influenced the scientists involved in The Lancet series to highlight this issue.

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Global Health, Public Health, Research, Stanford News

A moment in the sun for the tsetse fly – and the Stanford researcher studying its effect on Africa

A moment in the sun for the tsetse fly - and the Stanford researcher studying its effect on Africa

tsetse flyThanks to a study published earlier this year, the tsetse fly has garnered attention from The Economist, The Guardian, Humanosphere, and – most recently – from the Department of Medicine’s Annual Report.

What makes this flying pest so important? In the American Economic Review paper, Stanford’s Marcella Alsan, MD, PhD, showed that by spreading sleeping sickness the tsetse fly may have significantly affected Africa’s economic development.

In precolonial Africa, sleeping sickness killed livestock en masse in areas where the fly was prevalent. Alsan, a Stanford Health Policy core faculty member whose work focuses on the relationship between health and socioeconomic disparities, asserts that where cows and other livestock were not available in large numbers, farmers did not develop progressive agricultural methods. This produced lower crop yields and limited mobility for people and goods.

“Communicable disease has often been explored as a cause of Africa’s underdevelopment,” Alsan says in this Department of Medicine piece. “Although the literature has investigated the role of human pathogens on economic performance, it is largely silent on the impact of veterinary disease.”

Because fewer domesticated animals limited their transportation options and because sleeping sickness among humans thinned population densities, people living in tsetse-heavy areas of Africa were less likely to develop a centralized political system, making economic development more difficult. The lack of centralization continues to affect the continent today.

“The evidence suggests current economic performance is affected by the tsetse through the channel of precolonial political centralization,” Alsan wrote in the American Economic Review piece.

This work may help to determine why many African communities lack the development of wealthier countries. “It’s incredibly important to shine light on issues that are Africa-specific and therefore may not garner as much attention as those economic and medical issues that affect wealthier regions of the world,” Alsan noted.

Nicole Feldman is the communications associate at Stanford Health Policy.
Photo by David Dennis

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